This invention relates to teaching and more particularly to aids for teaching.
Learning, especially at the lower grade levels, is through the repetitive performance of a task such as spelling, mathematics, geography, etc. The student is taught how the task is performed by observing the instructor perform the same or similar task and thereafter attempting the task themselves. Traditionally, this teaching is accomplished via a blackboard or other such display on a wall. The instructor prints a problem and explains the steps of the solution. The students are supplied with paper worksheets that have similar problems.
Although the paper worksheets are inexpensive to print, for young students many mistakes are made before the task is correctly performed. These mistakes must be erased; on paper this causes rips, tears, and smudges which inhibits the student in the learning process.
The modern classroom recognizes that students are individuals and perform their tasks and learn new ones at varying speeds. In the modern classroom, many subjects permit the student to "self-pace" or learn the subject at a speed with which the student feels comfortable. This improved approach to teaching means that the instructor is faced with the situation that multiple lessons are being performed simultaneously within the class. Explaining a particular task on the blackboard is not only cumbersome but is disruptive. Students who are either behind the task being performed or ahead of it find the black-board work confusing and interruptive.
Recognizing that it is desirable to be able to use the worksheet itself as a visual reference, several devices have been made permitting the worksheet to be secured under a clear plate. By writing on the clear plate, the worksheet can be repeatedly completed without actually marking on the worksheet. One type of device, uses hinges and heavy materials to secure the worksheet squeezed between two plates. The plates, when opened and shut, are disruptive in the classroom and are difficult for small children to utilize. In another type of device, as described in the inventors U.S. Patent, the sheet is positioned on a clipboard and then is inserted between the two plates. This arrangement may damage the transparent surface of the holder by scratching it thus making more difficult to see the underlying worksheet. This construction also does not provide a means to ensure that the clipboard stays in place. The clipboard may slide out, causing damage or injury. A device that would securely hold the clipboard away from the transparent surface would be highly desirable.
Other devices use flexible sheets of clear plastic. However, the flexible plastic is not conducive to repeated writing and erasure and eventually the ink from the underlying paper is transferred to the plastic. This creates smudges on the plastic, diminishing the transparency of the plastic.